SIRS (Systemic Inflammatory Response Syndrome) is a systemic inflammatory response triggered by a variety of causes, infectious or not. When the SIRS is triggered by infectious causes, it is considered to be a SEPSIS. Among the states of SIRS triggered by non-infectious causes, mention may be made of all the stress factors which cause a systemic inflammatory response such as, for example, traumatic states, burns, pancreatitises, acute respiratory syndromes, major surgeries accompanied, or not, with cardiopulmonary bypass. The systemic inflammatory response manifests itself with at least two of the following signs: a) temperature above 38° C. or below 36° C.; b) heart rate above 90 beats per minute; c) breathing rate above 20 breaths per minute; d) leukocyte count above 12000/mm3 or below 4000/mm3, according to the defining criteria established by a group of experts in 2001 (M. M. Levy, M. P. Fink, J. C. Marshall, E. Abraham, D. Angus, D. Cook, J. Cohen, S. M. Opal, J. L. Vincent and G. Ramsay, 2001 SCCM/ESICM/ACCP/ATS/SIS International Sepsis Definitions Conference, Crit. Care Med. 31 (2003), pp. 1250-1256). Furthermore, the state of the patient presenting with SIRS is often made more complicated due to dysfunctions of one or several organs, and mostly because of an infectious complication which may be due to a pathogenic endogenous reactivation and/or nosocomial infections which can evolve toward an acute septic syndrome (SEPSIS, acute SEPSIS, septic shock). For all the reasons described above, SIRS patients present an increased risk of mortality, whereby death can occur at different stages of evolution of the SIRS. It is therefore necessary for the clinician to have available to him elements which enable him to determine whether the patient has a good or poor prognosis of survival. Indeed, identifying patient presenting high risks of mortality very early on after the beginning of a SIRS would enable the clinician to improve the success of a targeted and early care in intensive care by attributing adapted hospital resources and providing support to end-of-life medical decisions. Furthermore, identifying patients presenting a low risk of mortality could enable a clinician to anticipate their checking out of the intensive care unit to direct them toward a more suitable department, which is not negligible from an economic standpoint in terms of health management.